Polymer controlled induced viscosity fiber system and uses thereof

ABSTRACT

The present invention relates generally to a method of blunting the postprandial glycemic response in a human by feeding an induced viscosity fiber system. The invention also relates to an induced viscosity fiber system and the liquid products that incorporate the induced viscosity fiber system. Further, the invention relates to a method of incorporating soluble fiber into a liquid product without the typical negative organoleptic or physical stability issues. The invention also relates to a method of inducing the feeling of fullness and satiety by feeding the induced viscosity fiber system.

CROSS REFERENCE

This application is a continuation of U.S. patent application Ser. No.10/157,297, which was filed on May 29, 2002 now U.S. Pat. No. 7,067,498.

TECHNICAL FIELD

The present invention relates generally to a method of blunting thepostprandial glycemic response to a meal. The invention also relates toan induced viscosity fiber system and the liquid products thatincorporate the induced viscosity fiber system. Further, the inventionrelates to a method of incorporating soluble fiber into a liquid productwithout the typical negative organoleptic or physical stability issues.The invention also relates to a method of inducing the feeling offullness and satiety by feeding the induced viscosity fiber system.

BACKGROUND OF THE INVENTION

Diabetes is the seventh leading cause of death in the United States andthe sixth leading cause of death by disease among Americans. It isestimated that 15.7 million people, or 7.8% of the US population, sufferfrom diabetes. Consequently, the economic burden of diabetes is great,with an estimated total annual economic cost of $98 billion in 1997.This includes $44 billion for direct medical and treatment costs, and$54 billion for indirect costs due to disability and mortality.

The cause of diabetes is unknown, however, known risk factors for thisdisease are multi-factorial. Genetics and environmental factors such asobesity and sedentary lifestyle appear to contribute to diabetesincidence. Type 2 diabetes, a disorder resulting from the body'sinability to make enough or properly use insulin, accounts for 90 to 95percent of all diabetes. This type of diabetes is reaching epidemicproportions in America because of the increasing age of the population,in addition to a greater prevalence of obesity and sedentary lifestyles.

Standard treatment of diabetes involves maintenance of as near-normalblood glucose levels as possible by balancing food intake with insulinor oral glucose-lowering medications and physical activity levels. Lowcalorie diets and weight loss usually improve short-term glycemic levelsand have the potential to improve long-term metabolic control. However,traditional dietary strategies, and even very-low-calorie diets, haveusually not been effective in achieving long-term weight loss.

Obesity is associated with numerous chronic diseases, such as type 2diabetes, heart disease, hypertension, stroke, dyslipidemia,osteoarthritis, sleep apnea, gallbladder disorders, respiratoryproblems, and malignancy. A loss of only 5% to 10% of baseline weight inan obese patient with type 2 diabetes, hypertension, or dyslipidemia canimprove glycemic control, decrease blood pressure, and improve the lipidprofile, respectively. Lifestyle modification by changes in diet orincrease in exercise is usually the first step in treating overweight orobese persons. However, behavioral modification is often not verysuccessful, and long-term maintenance of diet or exercise changes isattained by less than 15% of persons who initiate these changes. Inaddition, restricted calorie diets cannot be continued over a longperiod of time, and the majority of the weight lost on these diets isre-gained.

One approach to initiating and maintaining weight loss in overweightindividuals is by inducing satiation (feeling of fullness during a meal)and satiety (feeling of fullness after a meal). Various gastrointestinalmechanisms trigger both the initiation and termination of eating inindividual persons. Although gastric distention is a normal sign of“fullness” and plays a role in controlling food intake, its effects aretemporary and distinct from feelings of satiety associated with a meal.Satiety is associated with postprandial sensations related to theactivation of intestinal chemoreceptors, such as cholecystokinin,leptin, insulin, hypothalamic neuropeptide Y, and glucocorticoidhormones. These postprandial sensations, which are largely responsiblefor the phenomenon of satiation after a meal is consumed, have alonger-lasting effect on satiety or hunger than gastric distention.

The concept that dietary fiber may aid in the treatment of hyperglycemiahas been suggested since the 1970's. Viscous soluble fiber (e.g., guargum, psyllium, oat β-glucan) supplementation to test meals has beenshown to effectively blunt postprandial glycemia. Despite the existenceof some in vivo evidence; however, there is still considerable doubtabout the efficacy of dietary fiber in the treatment of hyperglycemia.This doubt may exist because different types of dietary fibers havedifferent physiological effects. As analytical methods for dietary fiberimprove, so does our understanding of physiological fiber effects. Forexample, soluble viscous fibers generally have a greater effect oncarbohydrate metabolism in the small intestine by slowing the rate ofabsorption, although delayed gastric emptying also may play a role.These phenomena should decrease the rate at which glucose enters thesystemic circulation and delay the postprandial rise in blood glucose.While the applicability of this concept is evident, its clinical use islimited. Unfortunately, foodstuffs containing viscous fibers (e.g., guargum) usually exhibit slimy mouth-feel, tooth packing, and poorpalatability. The overall hedonic quality of guar-containing foods canbe improved by reducing the average molecular weight (e.g., throughchemical hydrolysis) of the galactomannan in guar gum; however, thisresults in a concurrent loss in clinical efficacy.

There are commercially available nutritional products that are designedto meet the nutritional needs of a diabetic while helping to maintaincontrol of their blood glucose level. The commercial products aretypically liquid and include higher amounts of fat. The higher fat isdesired in a liquid nutritional as the fat slows down stomach emptying,thereby delaying the delivery of nutrients to the small intestine, whichblunts the absorption curve of carbohydrates after a meal.

Glucerna® (Ross Products Division of Abbott Laboratories, Columbus Ohio)is a liquid nutritional with fiber for patients with abnormal glucosetolerance. Sodium and calcium caseinates make up 16.7% of total caloriesas protein; maltodextrin, soy polysaccharide and fructose make up 34.3%of total calories as carbohydrate; and high oleic safflower oil andcanola oil make up 49% of total calories as fat. Soy polysaccharidecontributes 14.1 g/1000 ml of total dietary fiber. The RDI for vitaminsand minerals is delivered in 1422 kcals. The product also contains theultra trace minerals selenium, chromium and molybdenum and theconditionally essential nutrients carnitine and taurine.

Choice dm® (Mead Johnson & Company, Evensville, Ind.) is a nutritionallycomplete beverage for persons with glucose intolerance. Milk proteinconcentrate makes up 17% of total calories as protein; maltodextrin andsucrose make up 40% of total calories as carbohydrate; and high oleicsunflower oil and canola oil make up 43% of total calories as fat.Microcrystalline cellulose, soy fiber and gum acacia contribute 14.4g/1000 ml of total dietary fiber. The RDI for vitamins and minerals isdelivered in 1060 kcals. The product also contains the ultra traceminerals selenium, chromium and molybdenum and the conditionallyessential nutrients, carnitine and taurine.

Resource® Diabetic (Sandoz Nutrition Corporation, Berne, Switzerland) isa complete liquid formula with fiber specifically designed for personswith type 1 and type 2 diabetes and for persons with stress-inducedhyperglycemia. Sodium and calcium caseinates, and soy protein isolatemake up 24% of total calories as protein; hydrolyzed corn starch andfructose make up 36% of total calories as carbohydrate; and high oleicsunflower oil and soybean oil make up 40% of total calories as fat.Partially hydrolyzed guar gum contributes 3.0 g/8 fl. oz. of totaldietary fiber. The RDI for vitamins and minerals is delivered in 2000kcals. The product also contains the ultra trace minerals selenium,chromium and molybdenum and the conditionally essential nutrientscarnitine and taurine.

Ensure® Glucerna® Shake (Ross Products Division of Abbott Laboratories,Columbus Ohio) is an oral supplement specifically designed for peoplewith diabetes. Sodium and calcium caseinates and soy protein isolatemake up 18% of total calories as protein; maltodextrin, fructose,maltitol, soy polysaccharide and FOS make up 47% of total calories ascarbohydrate; and high oleic safflower oil and canola oil make up 35% oftotal calories as fat. Soy polysaccharide and fructooligosaccharides(FOS) contribute 3.0 g/8 fl. oz. of total dietary fiber. At least 25% ofthe DV for 24 key vitamins and minerals are delivered in 8 fl. oz. Theproduct also contains the ultra trace minerals selenium, chromium andmolybdenum.

U.S. Pat. No. 4,921,877 to Cashmere et al. describes a nutritionallycomplete liquid formula with 20 to 37% of total caloric value from acarbohydrate blend that consists of corn starch, fructose and soypolysaccharide; 40 to 60% of total caloric value from a fat blend withless than 10% of total calories derived from saturated fatty acids, upto 10% of total calories from polyunsaturated fatty acids and thebalance of fat calories from monounsaturated fatty acids; 8 to 25% oftotal caloric value is protein; at least the minimum US RDA for vitaminsand minerals; effective amounts of ultra trace minerals chromium,selenium and molybdenum; and effective amounts of carnitine, taurine andinositol for the dietary management of persons with glucose intolerance.

U.S. Pat. No. 5,776,887 to Wibert et al. describes a nutritionalcomposition for the dietary management of diabetics containing a 1 to50% total calories protein; 0 to 45% total calories fat, 5 to 90% totalcalories carbohydrate system and fiber. The carbohydrate system requiresa rapidly absorbed fraction such as glucose or sucrose, a moderatelyabsorbed fraction such as certain cooked starches or fructose and aslowly absorbed fraction such as raw cornstarch.

U.S. Pat. No. 5,292,723 to Audry et al. describes a liquid nutritionalcomposition containing a lipid fraction, a protein fraction and aspecific combination of glucides useful as dietetics. The glucidefraction consists of glucose polymers and slowly absorbed glucides.

U.S. Pat. No. 5,470,839 to Laughlin et al. describes a composition andmethod for providing nutrition to a diabetic patient. The lowcarbohydrate, high fat enteral composition contains a protein source, acarbohydrate source including a slowly digested high amylose starch andsoluble dietary fiber, and a fat source that includes a high percentageof monounsaturated fats.

U.S. Pat. No. 5,085,883 to Garleb et al. describes a blend of dietaryfiber which includes by weight: 5% to 50% of a dietary fiber that isboth soluble and fermentable; 5% to 20% of a dietary fiber that is bothsoluble and non-fermentable; and 45% to 80% of a dietary fiber that isboth insoluble and non-fermentable. Preferably, the dietary fiber, whichis both soluble and fermentable, is gum arabic; the dietary fiber, whichis both soluble and non-fermentable, is sodium carboxymethylcellulose;and the dietary fiber, which is both insoluble and non-fermentable, isoat hull fiber.

U.S. Pat. No. 5,104,677 to Behr et al. describes a liquid nutritionalproduct that contains a fat source and a dietary fiber system. Thedietary fiber system as a whole includes by weight: (a) 5% to 50%dietary fiber which is both soluble and fermentable, 5% to 20% dietaryfiber which is both soluble and non-fermentable, and 45% to 80% dietaryfiber which is both insoluble and non-fermentable. Less than 10% of thetotal calories in the product comprise saturated fatty acids, no morethan 10% of the total calories in the product is polyunsaturated fattyacids, and the ratio of the n-6 to n-3 fatty acids in the product beingin the range of 2 to 10. Preferably the dietary fiber that is bothsoluble and fermentable, is gum arabic; the fiber that is both solubleand non-fermentable, is sodium carboxymethylcellulose, and the fiberthat is both insoluble and non-fermentable, is oat hull fiber.

The prior art describes multi-component carbohydrate systems that bluntthe glycemic response by requiring sources of carbohydrate that areabsorbed at different rates. These multi-component carbohydrate systemspossess physical characteristics that make incorporation of thecarbohydrate systems into nutritional formulas difficult. Additionally,these multi-component carbohydrate systems are often found to possessunacceptable organoleptic characteristics. For example, guar gumfunctions to provide viscosity in the stomach, thereby slowing therelease of nutrients to the small intestine. Unfortunately, foodstuffscontaining guar gum typically exhibit slimy mouth-feel, tooth packing,and poor palatability. Additionally, effective amounts of guar gumincrease the viscosity of liquid products such that the liquid productgels in the container. The overall hedonic quality of guar-containingfoods can be improved by reducing the average molecular weight (i.e.,through hydrolysis) of the galactomannan in guar gum; however, thisresults in a concurrent loss in clinical efficacy. In addition to thechallenge of making a palatable product, dietary supplementation witheffective levels of guar gum is also associated with gastrointestinalside effects (e.g., flatulence and diarrhea) from its colonicfermentation, because guar gum is a rapidly fermented carbohydrate.

Thus, a need has developed in the art for a fiber system which acts toblunt the absorption curve of carbohydrates after a meal, while beingwell tolerated, organoleptically acceptable and easily incorporated intonutritional matrixes. The formulation of these novel products thatattenuate the postprandial glycemic excursion would enhance the use ofnutrition as adjunctive therapy for people with diabetes mellitus.

The disease state of many diabetics is complicated by their overweightstatus. As described above, highly viscous digesta results in the slowrelease of nutrients to the small intestine. This slow release alsoinduces the feeling of fullness and satiety. For example, 9 to 20 gm/dayof supplemental guar gum for 4 to 8 weeks has been shown tosignificantly reduce body weight and sensations of hunger compared tocontrol. (Bruttomesso, D.; Briani, G.; Bilardo, G.; Vitale, E.;Lavagnini, T.; Marescotti, C.; Duner, E.; Giorato, C.; Tiengo, A. Themedium-term effect of natural or extractive dietary fibres on plasmaamino acids and lipids in type 1 diabetics. Diabetes Research andClinical Practice. 1989, 6, 149-155; Krotkiewski, M. Effect of guar gumon body-weight, hunger ratings and metabolism in obese subjects. Br. J.Nutr. 1984, 52, 97-105.) However, the same issues described above intolerance and product development apply to the use of soluble fiber toinduce the feeling of fullness and satiety. The commercial marketresponded to these organoleptic and product stability issues bymanufacturing guar gum capsules. However, safety issues surfaced whenthe capsules were found to stick and swell in the throat uponswallowing. The increased incidence of choking resulted in the guar gumcapsules being removed from the market.

Thus, a need has developed in the art for a fiber system that inducesthe feeling of fullness and satiety, while being well tolerated,organoleptically acceptable and easily incorporated into nutritionalmatrixes.

SUMMARY OF THE INVENTION

The inventors have discovered a novel fiber system that facilitatesincorporation of soluble, viscous fibers into a liquid product. Thenovel fiber system is clinically effective in blunting the glycemicresponse to a meal while addressing the negative organoleptic, toleranceand physical stability issues typically associated with soluble viscousfibers. This novel system will be referred to as the induced viscosityfiber system. It is based upon building viscosity in vivo by theindirect action of α-amylase. The inventors discovered a systemutilizing lightly hydrolyzed starch to prevent the dissolution of thesoluble fiber. A low-viscosity shelf-stable, liquid product containingthe induced viscosity fiber system of the instant invention was producedthat became highly viscous when α-amylase was added to the product (i.e.an polymer controlled induced viscosity fiber system beverage). Aproduct formulated with the induced viscosity fiber system of theinvention has a low viscosity in the absence of α-amylase, be“drinkable”, and become highly viscous following ingestion. It is uponingestion that salivary α-amylase hydrolyzes the starch thereby enablingthe fiber to solubilize and form a viscous digesta. Further, the inducedviscosity fiber system requires less soluble fiber than the prior art toobtain the same clinical effect, thereby decreasing the tolerance andproduct development issues typically associated with soluble fiber. Asdiscussed above, the induced fiber system of the instant invention wouldbe applicable to people with diabetes and those needing to lose weight.

The first embodiment of the present invention refers to a polymercontrolled induced viscosity fiber system. The first component of theinduced viscosity fiber system of the instant invention is neutralsoluble fiber. A second more soluble component is required for thepolymer induced viscosity fiber system of the instant invention tofunction. Typically, the preferred more soluble component is lightlyhydrolyzed starch. The concentration of the starch required to preventthe neutral soluble fiber from dissolving is inversely proportional tothe molecular weight of the starch.

The present invention also refers to a method of delivering solublefiber to diabetics and to persons needing to lose weight. The presentinvention also refers to a method of blunting the postprandial glycemicresponse by feeding induced viscosity fiber system. Additionally, theinvention refers to a method of promoting the feeling of fullness byfeeding the induced viscosity fiber system.

DESCRIPTION OF THE DRAWINGS

FIG. 1: Effect of carbohydrate molecular size and concentration on theviscosity of a guar gum solution. Maltodextrin with DP=25 (•) andmaltodextrin with DP=100 (∘) added to a 2% guar gum solution.

FIG. 2: Effect of heating and cooling on the viscosity of a 2% guar gumplus 10% DE 1 maltodextrin mixture.

FIG. 3: Effect on gastric emptying of control formula(♦), 0.78%glactomannan formula(▪) and 1.21% glactomannan formula(▴). *P<0.05 vscontrol; +P=0.095 vs control.

FIG. 4: Effects on the frequency of intestinal contractions of controlformula, 0.78% glactomannan formula and 1.21% glactomannan formula atbaseline(charcoal gray), 0-30 minutes(black), 31-60 minutes(white) and91-120 minutes(gray). *P<0.05 vs baseline.

FIG. 5: Effects on the strength of intestinal contractions of controlformula, 0.78% glactomannan formula and 1.21% glactomannan formula atbaseline(charcoal gray), 0-30 minutes(black), 31-60 minutes(white) and91-120 minutes(gray). *P<0.05 vs baseline; +P<0.05 vs control.

FIG. 6: Viscosity at a shear rate of 30 sec⁻¹ vs collection time ofcontrol formula(Δ), 0.78% glactomannan formula(♦) and 1.21% glactomannanformula(▪).

DETAILED DESCRIPTION OF THE INVENTION

As used in this application:

-   -   a. “glycemic index” (GI) is calculated by dividing the blood        glucose incremental area under the curve (AUC) of the test food        by the blood glucose AUC of the reference food and multiplying        by 100, where the available carbohydrate content of test and        reference foods are the same. The reference food is typically        glucose or white bread, which has the standard GI of 100.    -   b. “neutral water soluble fiber” refers to fiber that can be        dissolved in water and carries no charge at neutral pH.    -   c. “satiation” refers to the feeling of fullness during a meal.        Various gastrointestinal mechanisms trigger the termination of        eating in individuals. Although gastric distention is a normal        sign of “fullness” and plays a role in controlling food intake,        its effects are temporary and distinct from feelings of satiety        associated with a meal.    -   d. “satiety” refers to the feeling of fullness after a meal.        Satiety is associated with postprandial sensations related to        the activation of intestinal chemoreceptors, such as        cholecystokinin, leptin, insulin, hypothalamic neuropeptide Y,        and glucocorticoid hormones. These postprandial sensations,        which are largely responsible for the phenomenon of satiation        after a meal is consumed, have a longer-lasting effect on        satiety or hunger than gastric distention.    -   e. “soluble” and “insoluble” dietary fiber is determined using        American Association of Cereal Chemists (AACC) Method 32-07. A        “soluble” dietary fiber source refers to a fiber source in which        at least 60% of the dietary fiber is soluble dietary fiber as        determined by AACC Method 32-07, and an “insoluble” dietary        fiber source refers to a fiber source in which at least 60% of        the total dietary fiber is insoluble dietary fiber as determined        by AACC Method 32-07.    -   f. “fermentable” and “non-fermentable” dietary fiber is        determined by the procedure described in “Fermentability of        Various Fiber Sources by Human Fecal Bacteria In Vitro”, at        AMERICAN JOURNAL CLINICAL NUTRITION, 1991; 53:1418-1424. This        procedure is also described in U.S. Pat. No. 5,085,883 to Garleb        et al. “Non-fermentable” dietary fiber refers to dietary fibers        that have a relatively low fermentability of less than 40% by        weight, preferably less than 30% by weight, and the term        “fermentable” dietary fiber refers to dietary fibers which have        a relatively high fermentability of greater than 60% by weight,        preferably greater than 70% by weight.    -   g. the term “total calories” refers to the total caloric content        of a definitive weight of the finished nutritional product.    -   h. the term “Reference Daily Intakes or RDI” refers to a set of        dietary references based on the Recommended Dietary Allowances        for essential vitamins and minerals. The Recommended Dietary        Allowances are a set of estimated nutrient allowances        established by the National Academy of Sciences, which are        updated periodically to reflect current scientific knowledge.    -   i. the term “dextrose equivalence” (DE) refers to a quantitative        measure of the degree of starch polymer hydrolysis. It is a        measure of reducing power compared to a dextrose (glucose)        standard of 100. The higher the DE, the greater the extent of        starch hydrolysis. As the starch is further hydrolyzed (higher        DE), the average molecular weight decreases and the carbohydrate        profile changes accordingly. Maltodextrins have a DE less        than 20. Corn syrup solids have a DE of 20 or higher and are        more rapidly absorbed.    -   j. the term “degree of polymerization” (DP) refers to the number        of glucose units joined in the molecule. The higher the DP        average, the lesser the extent of starch hydrolysis. As the        starch is further hydrolyzed, the average molecular weight        decreases, the average DP decreases and the carbohydrate profile        changes accordingly. Maltodextrins have a greater DP than corn        syrup solids.    -   k. the term “starch” refers to the variety of cereal and root        starches that contain a mixture of amylose and amylopectin        starch molecules.    -   l. the term “lightly hydrolyzed starch” refers to a product        obtained by acid, enzyme or combined hydrolysis of starch        consisting of lower molecular weight polysaccharides,        oligosaccharides and/or monosaccharides. Hydrolyzed starches        typically include acid modified starches, acid thinned starches,        thin boiling starches, dextrins and maltodextrins. The lightly        hydrolyzed starches suitable for the instant invention typically        have a DP of at least about 10.    -   m. the term “in vivo viscosity” refers to the viscosity measured        by the addition of 20 μL of bacterial alpha-amylase (Sigma) to        250 gm of the polymer controlled induced viscosity fiber system        followed by shearing using a Glass-Col mixer for 30 minutes. The        viscosity following shearing is measured using a Brookfield        Viscometer (Model DV-II+) with a 62 spindle at room temperature.        The induced viscosity of nutritional products that contain the        polymer controlled induced viscosity fiber system is measured by        the addition of 20 μL of bacterial alpha-amylase (Sigma) to 250        gm of the nutritional product followed by shearing using a        Glass-Col mixer for 30 minutes. The viscosity following shearing        is measured using a Brookfield Viscometer (Model DV-II+) with a        62 spindle at room temperature.    -   n. the term viscosity is the ratio of shear stress to shear        rate, expressed as dynes-second/cm², or poise. A centipoise        (cps) is one hundredth of a poise. A poise is a unit of        coefficient of viscosity, defined as the tangential force per        unit area required to maintain one unit difference in velocity        between two parallel planes separated by one centimeter of        fluid. Any viscosity determination should be carried out using a        Brookfield Viscometer (Model DV-II+) with a 62 spindle at room        temperature. The viscosity is measured by operating the        viscometer at a spindle speed that is the highest speed possible        to obtain a reading that is on scale.    -   o. any reference to a numerical range in this application should        be construed as an express disclosure of every number        specifically contained within that range and of every subset of        numbers contained within that range. Further, this range should        be construed as providing support for a claim directed to any        number, or subset of numbers in that range. For example, a        disclosure of 1-10 should be construed as supporting a range of        2-8, 3-7, 5, 6, 1-9, 3.6-4.6, 3.5-9.9, 1.1-9.9, etc.    -   p. the terms “induced viscosity fiber system”, “polymer        controlled induced viscosity fiber system”, “polymer induced        viscosity fiber system” and “induced viscosity system” are used        interchangeably and refer to the instant invention.

Hydrophilic polymers compete for water for solubilization. When two ormore polymers are present in the same solution, the solubility of theless soluble polymer decreases as the concentration of the polymer withthe higher solubility increases. When the concentration of the highersoluble polymer reaches a critical level, the less soluble polymerbecomes insoluble. The advantage for a ready-to-feed (RTF) product is ahigh fiber content with a relatively low viscosity. The presentinvention relies on a “triggering” factor, that indirectly impacts thesolubility of a soluble fiber to create induced viscosity in vivo.

The first component of the induced viscosity fiber system of the instantinvention is neutral soluble fiber. Numerous types of dietary fibers areknown and available to one practicing the art. Fibers differsignificantly in their chemical composition and physical structure andtherefore their physiological functions. The dietary fiber sourcesutilized in this invention can be characterized by the term solubility.Fiber can be divided into soluble and insoluble types and fiber sourcesdiffer in the amount of soluble and insoluble fiber they contain.

Representative of soluble dietary fiber sources are gum arabic, sodiumcarboxymethylcellulose, methylcellulose, guar gum, gellan gum, locustbean gum, konjac flour, hydroxypropyl methylcellulose, tragacanth gum,karaya gum, gum acacia, chitosan, arabinoglactins, glucomannan, xanthangum, alginate, pectin, low and high methoxy pectin, β-glucans,carrageenan and psyllium. Numerous commercial sources of soluble dietaryfibers are readily available and known to one practicing the art. Forexample, gum arabic, carboxymethylcellulose, guar gum, xanthan gum,alginates, pectin and the low and high methoxy pectins are availablefrom TIC Gums, Inc. of Belcamp, Md. Oat and barley β-glucans areavailable from Mountain Lake Specialty Ingredients, Inc. of Omaha, Nebr.Psyllium is available from the Meer Corporation of North Bergen, N.J.while the carrageenan and konjac flour are available from FMCCorporation of Philadelphia, Pa.

Preferably, the soluble fibers of the instant invention are alsoneutral. Charged polymers are typically more soluble than neutralpolymers, thus, neutral polymers are preferred for this application.Representative of neutral soluble dietary fiber sources are guar gum,pectin, locust bean gum, methylcellulose, β-glucans, glucomannan, andkonjac flour.

All neutral water soluble fibers are suitable candidates for developingpolymer controlled induced viscosity products. For example, as describedin Experiment 3, the addition of maltodextrin drastically reduced theviscosities of locust bean gum, konjac flour, and methocel solutions.

The preferred neutral soluble fiber source is guar gum. Guar gum is aviscous, water-soluble dietary fiber composed of a β-1,4 mannosebackbone with galactose side chains linked α-1,6. This galactomannan isobtained from the endosperm of the seeds of the leguminous vegetable,Indian cluster bean, Cyamposis tetragonolobus. It is widely used in thefood industry as a stabilizer and as a thickening and film-formingagent.

A second more soluble component is required for the polymer inducedviscosity fiber system of the instant invention to function. Typically,the preferred more soluble component is lightly hydrolyzed starch. Theconcentration of the starch required to prevent the neutral solublefiber from dissolving is inversely proportional to the molecular weightof the starch. For example, as described in Experiment 1, 10% of thelarger molecular weight, DP 100, maltodextrin was sufficient to renderguar gum insoluble, while 15% of the smaller molecular weight, DP 25,maltodextrin was required to push the initially dissolved guar gum outof solution. Useful hydrolyzed starches of the instant inventiontypically comprise a DP of at least about 10, preferably of at leastabout 20, more preferably from about 40 to about 100.

Representative of suitable starch sources are cornstarch, potato starch,beet starch, rice starch, tapioca starch, and wheat starch andcombinations thereof. Numerous commercial sources of starch andhydrolyzed starch are readily available and known to one practicing theart. For example, maltodextrin, glucose polymers, hydrolyzed cornstarchare available from Cerestar in Hammond, Ind. Wheat, rice andcornstarches are available from Weetabix Company in Clinton, Mass.Potato starch is available from Staley Mfg. Company in Decatur, Ill.

Alternatively, hydrolyzed starch may be obtained by acid, enzyme orcombined hydrolysis of starch. One practicing the art would be aware ofsuitable hydrolysis methods. Typically, acid modified starches are madeby mild acid hydrolysis of starch. For example, granular starch issuspended in very dilute acid and held at a temperature below itsgelatinization temperature to yield an acid modified or thin boilingstarch. Maltodextrins are typically prepared by partial hydrolysis ofcornstarch with acids and enzymes. Dextrins are typically prepared by aprocess called pyrolysis, which involves a dry reaction with heat andacid.

Any single lightly hydrolyzed starch listed above, or any combinationthereof may be utilized for developing induced viscosity fiber system ofthe instant invention. The ratio of neutral soluble fiber to lightlyhydrolyzed starch is from about 0.35:5.0 to about 1:5.0, preferable fromabout 0.7:5.0 to about 1:5.0, more preferable about 1:5.0. Examples ofsuitable induced viscosity fiber systems include one part guar gum/fivepart DP100 maltodextrin; 0.35 part konjac flour/five part DP 100maltodextrin; and 0.7 part guar gum/1.7 part DP100 maltodextrin/3.3 partDP25 maltodextrin.

Upon digestion, the induced viscosity fiber system is exposed toα-amylase, which begins to digest the lightly hydrolyzed starch,enabling the neutral soluble fiber to become solubilized. The inducedviscosity fiber system of the instant invention generates a viscousdigesta resulting in the slow release of nutrients into the smallintestine. The slow release of nutrients into the small intestineresults in prolonged absorption of nutrients, thereby blunting theglycemic response to the meal. The viscosity generated in vivo by thepolymer controlled induced viscosity fiber system is at least about 300cps, preferably at least about 1000 cps.

The induced viscosity fiber system has been designed to generate optimalviscosity in vivo while minimizing the ready-to-feed viscosity. Asdiscussed previously, the more soluble lightly hydrolyzed starch forcesthe neutral soluble fiber out of solution, thereby producing anacceptable drinkable product. The ready-to-feed viscosity of the polymercontrolled induced viscosity fiber system is less than about 300cps,preferably less than about 200 cps, more preferably from about 50 cps toabout 150 cps.

Typically the induced viscosity fiber system will be incorporated intofood products and consumed by the diabetic during their meals or snack.If desired, the diabetic may simply modify the recipe of foods theynormally consume. They may simply add the induced viscosity fiber systemand thereby reduce the glycemic index of the food. A similar strategymay be utilized by individuals attempting to lose weight because theslow release of nutrients also induces the feeling of fullness andsatiety.

Typically, the induced viscosity fiber system will be incorporated intomeal replacement beverages such as Glucerna®, Ensure®, Choice DM®, SlimFast®, Pediasure®, Glytrol®, Resource® Diabetic, etc. Methods forproducing such food products are well known to those skilled in the art.The following discussion is intended to illustrate such diabetic andweight loss meal replacement products and their preparation.

The nutritional formulas of this invention are designed to be used as ameal replacement or as a supplement. Because the product can be used asa meal replacement it will contain a protein source, a lipid source, acarbohydrate source, and vitamins, and minerals. Such amounts are wellknown by those skilled in the art and can be readily calculated whenpreparing such products. While these meal replacement products may serveas the sole source of nutrition, they typically don't. Individualsconsume these products to replace one or two meals a day, or to providea healthy snack. The nutritional products of this invention should beconstrued to include any of these embodiments.

The amount of these nutritional ingredients can vary widely dependingupon the targeted patient population (i.e. diabetics vs. non-diabetics,organoleptic considerations, cultural preferences, age group, use,etc.). Although not intended to limit the invention in any manner, butto merely serve as a general guideline, the nutritional formulas of thisinvention will typically provide the following caloric distribution. Theprotein system will typically provide from about 10% to about 35% oftotal calories, more preferably from about 15% to about 25% of totalcalories. The lipid system will provide less than about 37% of totalcalories, more preferably about 10% to about 30% of total calories. Thecarbohydrate system will typically provide from about 25% to about 75%of total calories, more preferably from about 35% to about 70% of totalcalories.

The novelty of these meal replacement products is the incorporation ofthe induced viscosity fiber system described above to generate a viscousdigesta. As noted above, the carbohydrate will provide from about 25 toabout 75% of total calories. Sufficient induced viscosity fiber systemshould be incorporated into the product so that the induced viscosityfiber system will comprise at least 10 w/w % of the carbohydrate system(when measured on a dry weight basis, i.e. not dissolved in a liquid).More typically, the induced viscosity fiber system will comprise fromabout 30 to about 60 w/w % of the carbohydrate system.

The remaining portion of the carbohydrate system may be provided by anycarbohydrate system suitable for humans, taking into account anyrelevant dietary restrictions (i.e. if intended for a diabetic).Examples of suitable carbohydrates that may be utilized include glucosepolymers, sucrose, maltitol, corn syrup solids, glucose, fructose,lactose, sugar alcohols, honey and high fructose corn syrup.

In addition to the carbohydrates described above, the nutritionals mayalso contain indigestible oligosaccharides such asfructooligosaccharides (FOS). Indigestible oligosaccharides are rapidlyand extensively fermented to short chain fatty acids by anaerobicmicroorganisms that inhabit the large bowel. These oligosaccharides arepreferential energy sources for most Bifidobacterium species, but arenot utilized by potentially pathogenic organisms such as Clostridiumperfingens, C. difficile, or E. coli. The term “indigestibleoligosaccharide” refers to a small carbohydrate moiety with a degree ofpolymerization less than or equal to about 20 and/or a molecular weightless than or equal to about 3,600, that is resistant to endogenousdigestion in the human upper digestive tract.

The meal replacement products also typically contain a protein source.The proteins that may be utilized in the nutritional products of theinvention include any proteins suitable for human consumption. Suchproteins are well known by those skilled in the art and can be readilyselected when preparing such products. Examples of suitable proteinsthat may be utilized typically include casein, whey, milk protein, soy,pea, rice, corn, hydrolyzed protein and mixtures thereof. Commercialprotein sources are readily available and known to one practicing theart. For example, caseinates, whey, hydrolyzed caseinates, hydrolyzedwhey and milk proteins are available from New Zealand Milk Products ofSanta Rosa, Calif. Soy and hydrolyzed soy proteins are available fromProtein Technologies International of Saint Louis, Mo. Pea protein isavailable from Feinkost Ingredients Company of Lodi, Ohio. Rice proteinis available from California Natural Products of Lathrop, Calif. Cornprotein is available from EnerGenetics Inc. of Keokuk, Iowa.

One skilled in the art must consider the solubility of the proteinsource when selecting an appropriate protein source. For example, asdescribed in Experiment 4, soluble proteins such as sodium caseinate cannegatively impact the in vivo induced viscosity and insoluble proteinssuch as milk protein isolate can increase the induced viscosity.

The third component of the nutritional products of this invention is thefat. The fat source for the present invention may be any fat source orblend of fat sources suitable for human consumption. As noted above, thefat source of this invention will typically provide less than or equalto 37% of the total calories. The fat source for the present inventionmay be any fat source or blend of fat sources that provides the desiredlevels of saturated (less than 10% kcal), polyunsaturated (up to 10%kcal) and monounsaturated fatty acids (10% to 37% kcal). One skilled inthe art can readily calculate how much of a fat source should be addedto the nutritional product in order to deliver the desired levels ofsaturated, polyunsaturated and monounsaturated fatty acids. Examples offood grade fats are well known in the art and typically include soy oil,olive oil, marine oil, sunflower oil, high oleic sunflower oil,safflower oil, high oleic safflower oil, flaxseed oil, fractionatedcoconut oil, cottonseed oil, corn oil, canola oil, palm oil, palm kerneloil and mixtures thereof.

Numerous commercial sources for the fats listed above are readilyavailable and known to one practicing the art. For example, soy andcanola oils are available from Archer Daniels Midland of Decatur, Ill.Corn, coconut, palm and palm kernel oils are available from PremierEdible Oils Corporation of Portland, Oreg. Fractionated coconut oil isavailable from Henkel Corporation of LaGrange, Ill. High oleic safflowerand high oleic sunflower oils are available from SVO Specialty Productsof Eastlake, Ohio. Marine oil is available from Mochida International ofTokyo, Japan. Olive oil is available from Anglia Oils of NorthHumberside, United Kingdom. Sunflower and cottonseed oils are availablefrom Cargil of Minneapolis, Minn. Safflower oil is available fromCalifornia Oils Corporation of Richmond, Calif.

The nutritional compositions of the invention desirably contain vitaminsand minerals. Vitamins and minerals are understood to be essential inthe daily diet. Those skilled in the art appreciate that minimumrequirements have been established for certain vitamins and mineralsthat are known to be necessary for normal physiological function.Practitioners also understand that appropriate additional amounts ofvitamin and mineral ingredients need to be provided to nutritionalcompositions to compensate for some loss during processing and storageof such compositions. Additionally, the practitioner understands thatcertain micronutrients may have potential benefit for people withdiabetes such as chromium, carnitine, taurine and vitamin E and thathigher dietary requirements may exist for certain micro nutrients suchas ascorbic acid due to higher turnover in people with diabetes.

An example of the vitamin and mineral system for a nutritionalformulation used as a meal replacement typically comprises at least 20%of the RDI for the vitamins A, B₁, B₂, B₆, B₁₂, C, D, E, K,beta-carotene, biotin, folic acid, pantothenic acid, niacin, andcholine; the minerals calcium, magnesium, potassium, sodium,phosphorous, and chloride; the trace minerals iron, zinc, manganese,copper, and iodine; the ultra trace minerals chromium, molybdenum,selenium; and the conditionally essential nutrients m-inositol,carnitine and taurine in a single serving or from about 50 Kcal to about1000 Kcal.

Artificial sweeteners may also be added to the nutritional formula toenhance the organoleptic quality of the formula. Examples of suitableartificial sweeteners include saccharine, aspartame, acesulfame K andsucralose. The nutritional products of the present invention will alsodesirably include a flavoring and/or color to provide the nutritionalproducts with an appealing appearance and an acceptable taste for oralconsumption. Examples of useful flavorings typically include, forexample, strawberry, peach, butter pecan, chocolate, banana, raspberry,orange, blueberry and vanilla.

The nutritional products of this invention can be manufactured usingtechniques well known to those skilled in the art. While manufacturingvariations are certainly well known to those skilled in the nutritionalformulation arts, a few of the manufacturing techniques are described indetail in the Examples. The manufacturing process is such to minimizethe exposure of the soluble fiber to heat and shear to preserve thefunctionality. Generally speaking an oil blend is prepared containingall oils, any emulsifier, stabilizer and the fat soluble vitamins. Threemore slurries (protein and two carbohydrate) are prepared separately bymixing a part of the carbohydrate and minerals together, the remainingcarbohydrate with the fiber and the protein in water. The protein inwater and carbohydrate/mineral slurries are then mixed together with theoil blend. The resulting mixture is homogenized, heat processed,standardized with water soluble vitamins, flavor and thecarbohydrate/fiber blend. The final blend is homogenized and asepticallyfilled in to appropriate containers. Alternatively, the homogenizedformula may be kept undiluted and dried to form powder. The product isthen packaged. Typically the package will provide directions for use bythe end consumer (i.e. to be consumed by a diabetic, to assist withweight loss, etc.).

A third embodiment of the instant invention is a method of blunting thepostprandial glycemic response in a human by feeding the inducedviscosity fiber system described above. The inventors discovered, inExperiment 5, that the polymer controlled induced viscosity fiber systemprovided a means to maintain blood glucose levels by reducing the earlyphase excursion and by appropriately maintaining the later phaseexcursion in healthy nondiabetic humans.

A fourth embodiment of the instant invention is a method of promotingthe feeling of fullness in a human by feeding the induced viscosityfiber system described above. The inventors discovered, in Experiment 6,that nutritional products containing two levels of the polymercontrolled induced viscosity fiber system (0.78% galactomannan and 1.21%galactomannan) delayed gastric emptying when compared to the control.

The embodiments of the present invention may, of course, be carried outin other ways than those set forth herein without departing from thespirit and scope of the invention. The present embodiments are,therefore, to be considered in all respects as illustrative and notrestrictive and that all changes and equivalents also come within thedescription of the present invention. The following non-limitingExamples will further illustrate the present invention.

Experiment 1

Initial experimentation involved the viscosity measurements of variouslevels of hydrolyzed maltodextrin in a 2% guar gum solution.

A 2% guar gum solution was prepared by dispersing the dry gum powder inwater using a Waring blender at high speed for 30 seconds. The resultingmixture was allowed to rest for at least 4 hours to allow the entrainedair to escape. Graded amounts of various maltodextrins were added to thevortex of a 2% guar gum solution in a Waring blender. The viscosities ofthe mixtures were measured using a Brookfield Viscometer (Model DV-II+)with a 62 spindle at room temperature immediately after themaltodextrins were dispersed.

The solubility of guar gum was depressed to varying degrees by theaddition of maltodextrins as indicated by the decrease in viscosity inFIG. 1. The effectiveness of maltodextrins in reducing the viscosity ofthe guar gum solution was inversely correlated with the molecular weightof the maltodextrin. As seen in FIG. 1, 10% of the larger molecularweight, DP 100, maltodextrin was sufficient to render guar gum insolublewhile it took 15% of the smaller molecular weight, DP 25, maltodextrinto push the initially dissolved guar gum out of solution.

Experiment 2

The 10% DP 100 maltodextrin (Steer DR1 is a commercial DE1 maltodextrinfrom AE Staley Company) and 2% guar gum solution from Experiment 1 washeated to 95° C. and then allowed to cool to room temperature. Theviscosity was monitored during the heating and cooling cycle using aBrookfield Viscometer (Model DV-II+) with a 62 spindle at roomtemperature (FIG. 2). The viscosity of the maltodextrin/guar gumdispersion was reduced from over 170 cpc to about 80 cps after heatingand cooling to room temperature. Heat helped to drive the guar gum outof solution thereby decreasing the viscosity.

Twenty micro liters of bacterial alpha amylase (Sigma) was added to 250gm of the maltodextrin/guar gum dispersion followed by shearing using aGlass-Col mixer for 30 minutes. The viscosity following shearing wasmeasured using a Brookfield Viscometer (Model DV-II+) with a 62 spindleat room temperature. The viscosity of the maltodextrin/guar gumdispersion increased to over 14,000 cps after the mixture was treatedwith alpha-amylase.

Experiment 3

Maltodextrin (15% DP100) was added to various neutral gum solutions andthe viscosities of the resultant mixtures were measured. Locust beangum, Konjac flour, and methocel 2% solutions were prepared by dispersingthe dry gum powder in water using a Waring blender at high speed for 30seconds. The resulting mixtures were allowed to rest for at least 4hours to allow the entrained air to escape. The viscosity of themixtures were measured using a Brookfield Viscometer (Model DV-II+) witha 62 spindle at room temperature. The maltodextrin (15% DP100) was addedto the vortex of each solution in a Waring blender. The viscosities ofthe mixtures were measured using a Brookfield Viscometer (Model DV-II+)with a 62 spindle at room temperature immediately after the maltodextrinwas dispersed.

The addition of maltodextrin drastically reduced the viscosities oflocust bean gum, konjac flour and methocel solutions. The viscosity ofthe locust bean gum solution dropped form 4000 cps to 1340 cps. Theviscosity of the methocel solution dropped from 1370 cps to 28 cps. The2% knojac flour solution gelled, however the addition of maltodextindropped the viscosity to 363 cps.

Additionally, the viscosity of locust bean gum/maltodextrin solution wasabout 1000 cps, which decreased to less than 100 cps after thedispersion was allowed to rest overnight. These findings indicated thatthe time for the dissolved polymer to come out of solution may vary butall neutral water soluble polymers are suitable candidates fordeveloping polymer controlled induced viscosity products.

Experiment 4

Various proteins (4.4% by weight) were added to a model systemcontaining 0.13% K-citrate, 0.15% Na-citrate, 0083% K₂HPO₄, 9.4% DP 100maltodextrin and 1% guar gum at room temperature under vigorousagitation. The viscosity of the mixtures were measured using aBrookfield Viscometer (Model DV-II+) with a 62 spindle at roomtemperature. The mixtures were autoclaved (120° C. for 30 minutes),allowed to cool, then digested with alpha-amylase. Twenty micro litersof bacterial alpha amylase (Sigma) was added to 250 gm of the autoclavedmixtures followed by shearing using a Glass-Col mixer for 30 minutes.The viscosity following shearing was measured using a BrookfieldViscometer (Model DV-II+) with a 62 spindle at room temperature (Table1).

TABLE 1 Effect of protein source on the development of viscosity W/OAfter Enzyme Protein Source Enzyme (cps) (cps) No protein 29.0 14,000Insoluble casein 72.5 >>15,000 Insoluble milk protein isolate95.5 >>15,000 Soluble casein 104 >15,000 Insoluble soy protein125 >15,000 Soluble sodium caseinate 166 380 Soluble whey 150 350

All of the soluble proteins, with the exception of soluble casein(Alanate 166 from New Zealand Milk Products in Santa Rosa, Calif.),reduced the induced viscosity of the unsterile model systems. Thesoluble proteins form large aggregates after autoclaving. A Warringblender was used to break down the aggregates. Surprisingly, thesterilized model systems containing sodium caseinate or whey proteinproduced a low induced viscosity (less than 400 cps) after alpha-amylasedigestion. The viscosities of the alpha-amylase digested model systemscontaining sodium caseinate increased to 2,800 cps after it wassubsequently digested with Pronase (a mixture of proteases from Sigma).Apparently, some of the guar gum was trapped in the protein aggregatesduring autoclaving. The trapped guar gum was released after the proteinaggregates were broken down by the Pronase. However, the fact that theinduced viscosity of the Pronase digested model system was lower thanthat of the unsterile model (2,800 vs 4,700 cps) lead the inventors tosuspect that a portion of the guar gum molecules were hydrolyzed duringthe autoclaving. To test this, the model system without protein wasautoclaved twice. The resulting induced viscosity was reduced from14,000 cps to 4,100 cps after going through the additional autoclavecycle, confirming that some of the guar gum was degraded duringretorting. Thus, a short exposure to heat is preferred to maximize theinduced viscosity.

Addition of an insoluble protein such as milk protein isolate to theguar/maltodextrin model system increased the induced viscosity. Theinsoluble protein particles absorb a lot of water and increase theeffective volume fraction of solids, thus producing a positive impact onthe viscosity of the dispersion. The preferred protein system is a blendof soluble and insoluble protein.

It is well known in the art that mechanical shear can cause hydrocolloidmolecules to degrade. The autoclaved model system was sheared using atissue grinder for one minute and found that the shearing reduced theinduced viscosity over 30,000 cps to less than 4,000 cps. Therefore, themanufacturing process is such to minimize the exposure of guar gum toheat and shear to preserve the guar gum functionality.

EXAMPLE I

The process for manufacturing 453.6 kg of a liquid nutritionalcontaining the polymer controlled induced viscosity fiber system of theinvention is described below. Most of the DE 1 maltodextrin was withheldfrom the carbohydrate/mineral slurry. The guar gum was added atstandardization as a guar gum/maltodextrin dispersion to minimizeexposure to heat and shear. Because the maltodextrin prevents the guargum from dissolving, it was possible to produce a maltodextrin/guar gumdispersion with a manageable viscosity. Further, the addition of the DE1 maltodextrin at standardization prevented the mix from forming a gelin the finished product tank (DE 1 maltodextrin can retrograde and forma gel at 4° C. if the concentration exceeds 3%).

The required amount of ingredients (Table 2) for the fat blend werecombined and held.

TABLE 2 Fat Blend High Oleic Safflower Oil 8.2 kg Canola Oil 0.95 kg SoyLecithin 0.49 kg Vitamin DEK premix* 30.87 gm Beta Carotene 30% 3.63 gmVitamin A Palmitate 3.41 gm Gum Arabic 1.7 kg *per gm Vitamin DEKpremix: 8130 IU vitamin D₃, 838 IU vitamin E, 1.42 mg vitamin K₁

The required amount of ingredients (Table 3) for the protein in waterslurry were combined. The pH was adjusted to 6.6-6.8 using 1N KOH. ThepH adjusted blend was held.

TABLE 3 Protein in Water Slurry Water  177 kg Milk Protein Isolate 12.8kg Sodium Caseinate   32 kg

The required amount of ingredients (Table 4) for thecarbohydrate/mineral slurry were combined and the pH was adjusted to6.6-6.8 using 1N KOH. The pH adjusted blend was held.

TABLE 4 Carbohydrate/Mineral Slurry Water 29 kg Maltodextrin DE 1 11 kgFructose 2.7 kg Micronized TCP 1.3 kg Magnesium Chloride 1.1 kg SodiumCitrate 1.1 kg Potassium Phosphate Dibasic 0.99 kg Magnesium PhosphateDibasic 0.54 kg Potassium Citrate 363.2 gm UTM/TM Premix* 172.5 gmPotassium Iodide 0.11 gm *Per gm of UTM/TM premix: 83 mg zinc, 65 mgiron, 18 mg manganese, 7.8 mg copper, 0.262 mg selenium, 0.365 mgchromium, 0.585 molybdenum.

After each slurry was prepared, the carbohydrate/mineral slurry wasadded to the protein in water slurry. The blend pH was adjusted to6.6-6.8. The fat blend was then added. The final blend was processed atUHT temperatures (295° F. for 5 seconds) and homogenized at 4000 psi.

The required amount of ingredients (Table 5) for the vitamin solutionwere combined and the pH was adjusted to 6.5-7.5 using 45% KOH. The pHadjusted blend was held.

TABLE 5 Vitamin Solution Water 8.5 kg Ascorbic Acid 227 gm CholineChloride 181.6 gm L-Carnitine 49.9 gm WSV Premix* 40.9 gm Taurine 45.4gm Sucralose 74.9 gm Vanilla Flavor 2.0 kg *per gm of WSV premix: 375 mgniacinamide, 242 mg calcium pantothenate, 8.4 mg folic acid, 62 mgthiamine chloride, 48 mg riboflavin, 59 mg pyridoxine hydrochloride, 165mcg cyanocobalamin, and 7305 mcg biotin

The vitamin solution was added to the processed blend atstandardization. The required amount of ingredients (Table 6) for the1.3% guar gum solution were combined and held.

TABLE 6 Guar Gum Solution Water 113 kg Maltodextrin DE1  25 kg Guar Gum 6 kg

The guar gum solution was added to the standardized blend. Guar gum wasadded to the maltodextrin solution under high agitation to prevent buildup of excessively high viscosity and guar gum lumps. Failure to disperseguar gum properly caused flow problems in the aseptic filling unit. Thefinal blend was UHT heated to 295° F. for 5 seconds and homogenized at1000 psi and aseptically filled into sterile 32 oz bottles.

The product manufactured as described above had an initial viscosity of120 cps and developed an induced viscosity of over 14,000 cps upontreatment with alpha amylase.

Experiment 5

The primary objective of this study was to evaluate the efficacy of apolymer controlled induced viscosity fiber system (IV) on theattenuation of the postprandial glycemic excursion to a low DEmaltodextrin beverage plus white bread (rapidly digested starches) inhealthy nondiabetic individuals. A secondary objective was to evaluatethe subjective gastrointestinal tolerance of subjects consuming apolymer controlled induced viscosity fiber system containing test meal.As an exploratory objective, the effects of a polymer controlled inducedviscosity fiber system on satiety was evaluated.

This study was a randomized, double-blind, two group,placebo-controlled, crossover, single center study. Subjectsparticipated in four 3-h meal glucose tolerance tests (MGTT) on separateoccasions. Subjects were randomly assigned to treatment sequences. Afteran overnight fast, subjects consumed 50 g available carbohydrate (25 gfrom DE 1 maltodextrin and 25 g from white bread) as the MGTT. Two DE 1maltodextrin beverages were formulated to test the effects of thepolymer controlled induced viscosity fiber system.

To ensure that subjects had similar glycogen stores on the 4 test days,subjects were instructed to consume a high carbohydrate diet (minimum150 g carbohydrate per day) for 3 d before each meal glucose tolerancetest and were also asked to avoid exercise 24 h before the experiment.On the evening before each meal glucose tolerance test, all subjectsconsumed a low-residue dinner consisting of one 8 fl oz (237 ml) can ofchocolate Ensure Plus® (Ross Products, Columbus, Ohio) with additionalHoney Graham Crunch Ensure®) Bars (Ross Products, Columbus, Ohio) toprovide one-third of each subject's individual daily caloric requirementas estimated by the Harris-Benedict equation multiplied by an activityfactor of 1.3. Subjects were instructed to fast overnight, followingtheir low-residue evening meal, during which they were only allowed toconsume water. Smoking was prohibited. On the morning of each mealglucose tolerance test, body weight, body temperature, pulse rate andblood pressure were measured by standard procedures. A fastingfinger-prick capillary blood sample was obtained and collected intofluoro-oxalate tubes after 30 min of rest. Subjects then consumed theappropriate test meal within 10 min. Finger-prick capillary blood wasobtained at 0, 15, 30, 45, 60, 90, 120 and 180 minutes postprandial.Samples were stored at −20° C. for a maximum of 3 d until analysis ofwhole blood glucose. Whole blood glucose was analyzed by the glucoseoxidase method utilizing a YSI analyzer (model YSI 2300 STAT PLUS,Yellow Springs Instruments, Yellow Springs, Ohio). Subjects were allowed8 fl oz water (240 ml) during each 2-h test. Immediately following eachtrial body temperature, pulse rate and blood pressure were measured.Subjects returned on average within 9 d (range 5 to 42 d) for repeatanalysis with the appropriate crossover treatment.

Using a questionnaire, subjects were asked to report the frequency andintensity of the following symptoms: nausea, cramping, distention, andflatulence for the 24-h period immediately following consumption of thetest material. Intensity and frequency was set to a 100-mm linear visualanalogue scale (0 representing “Absent” and 100 “Severe” and 0representing “Usual” and 100 “More than usual,” respectively). Subjectsplaced a single perpendicular slash mark across the 100 mm horizontalline to indicate their scores for each of these variables of frequencyand intensity. A score of 5 or less was considered not physiologicallymeaningful.

In order to assess the subjective feeling of hunger, subjects completeda satiety questionnaire immediately before the MGTT, at 1, 2, and 3 hpostprandial, and immediately before and after their lunch meal afterthe MGTT. Subjects rated their feeling of hunger with the followingscale: 1=not at all hungry; 3=slightly hungry; 5=moderately hungry;7=very hungry; 9=extremely hungry. In addition, subjects reported theamount of lunch consumed as: much less than usual, moderately less thanusual, somewhat less than usual, slightly less than usual, about thesame, slightly more than usual, somewhat more than usual, moderatelymore than usual, or much more than usual.

Subjects were between 18 and 75 years of age, inclusively, were male ora non-pregnant female at least 6 weeks postpartum and nonlactating, werenot currently receiving oral contraceptives, had a body mass index (BMI)between 20 and 28 kg/M², did not have diabetes mellitus or glucoseintolerance (baseline serum glucose<110 mg/dl (6.11 mmol/L)), did nothave a family history (first degree relatives) of diabetes mellitus orglucose intolerance, were free from active metabolic or gastrointestinaldiseases that may interfere with nutrient absorption, distribution,metabolism, or excretion and had no known food allergies, had no recent(<3 months) infections, surgeries or corticosteroid treatment and werenot under a high level of stress, were willing to consume Ensure® Plusand Ensure® Bar(s) as the evening meal on the day prior to test; werewilling to fast (10 hours) prior to testing and were willing to consumethe product within a 10-minute period; abstained from exercise 24 hoursprior to testing and minimized activity during the test; were not takingdaily medications (e.g., acetaminophen, salicylates, diuretics, etc.)that would interfere with nutrient absorption, metabolism, excretion orgastric motility; and had voluntarily signed an informed consent formprior to any participation in the study.

Subjects consumed 50 g available carbohydrate: 25 g from DE 1maltodextrin (Star D, A.E. Staley Manufacturing Co., Decatur, Ill.) and25 g from white bread as the MGTT. Two DE 1 maltodextrin-based beverageswere formulated to test the effects of the polymer controlled inducedviscosity fiber system (Table 7).

TABLE 7 Composition of Products Control IV Ingredient composition g/100g product Water 89.39 87.31 DE 1 maltodextrin 10.42 10.42 Guar gum 02.08 Fructose 0 0 Orange flavor 0.12 0.12 Sucralose 0.07 0.07 Proximateanalysis g/100 g product Total solids 9.5 11.8 Carbohydrate 9.5 11.7Fructose 0 0 TDF 0 1.80 Galactomannan 0 1.53 Nutrient g/240 g servingFructose 0 0 TDF 0 4.32 Galactomannan 0 3.67 Maltodextrin by difference22.80 23.76 Viscosity, cps 8 156

White bread was made from the following recipe: 250 ml warm water, 334 gall purpose flour (e.g., Robin Hood), 7 g sugar (sucrose), 4 g salt, 6.5g dry instant yeast. The bread maker was set for a 2 h bake, and turnedon. After the bread was made, it was removed from the container, set for1 h, and weighed. Each loaf contained 250 g carbohydrate, giving ten25-g carbohydrate portions. The end crusts were discarded, so eightportions were available for the meal glucose tolerance test.

The primary variable was the peak incremental change from baseline inblood glucose concentration.

The secondary variables were positive incremental area under the glucosecurve, time to peak blood glucose concentration, and the incrementalchange from baseline in blood glucose concentration at individual timepoints.

The supportive variables were: demographic variables [age, sex, race,and expected energy expenditure (kcal/d)]; anthropometric variables[height, weight, and BMI (computed centrally)]; intensity and frequencyof gastrointestinal intolerance symptoms (nausea, cramping, distention,and flatulence); glycemic index; percentage of subjects with a positivebreath hydrogen test; breath hydrogen and methane concentration atindividual time points; daily medications; and satiety factors.

Subjects had a mean (±SE) age of 51±3 years (range: 18 to 75 years),weight of 68.4±1.8 kg (range: 55.4 to 84.0 kg), and body mass index of24.2±0.4 kg/m² (range: 20.2 to 27.9 kg/m²). Subjects did not have activegastrointestinal or metabolic diseases, a first-degree family history ofdiabetes mellitus or glucose intolerance, recent infection, surgery orcorticosteroid treatment. No subjects were receiving oralcontraceptives.

Results

Table 8 presents data for incremental (i.e., change from baseline) peakglucose concentration, positive incremental area under the glucosecurve, time to peak glucose concentration, and glycemic index.

TABLE 8 Subjects consuming novel carbohydrate beverages in a mealglucose tolerance test Treatment Control IV Incremental peak  4.2 ±0.28^(a)  2.2 ± 0.16^(b) glucose (mmol/L)^(‡) Time to peak (min)^(‡)  42 ± 2.3^(b)   68 ± 5.0^(a) Incremental AUC 283 ± 22^(a) 215 ± 19^(b)(mmol · min/L)^(‡) Glycemic index^(§) 100  80 ± 5.8 *Mean ± SEM.^(‡)Treatment effect, P < 0.01. ^(§)Glycemic index = incremental AUC fortreatment/incremental AUC for control ^(a,b)Means in the same row withunlike superscript letters differ (P < 0.05).

The mean fasting blood glucose concentration was not different betweentreatments. Peak incremental blood glucose concentration was lower(P<0.05) when subjects consumed the test meal containing polymercontrolled induced viscosity fiber system compared with the Control.Incremental area under the glucose curve was lower (P<0.05) whensubjects consumed the polymer controlled induced viscosity fiber systemcontaining products compared with when subjects consumed Control. Timeto peak glucose concentration was delayed (P<0.05) when subjectsconsumed IV compared with the Control. The glycemic index was 80±5.8 forpolymer controlled induced viscosity fiber system. When subjectsconsumed test meals containing polymer controlled induced viscosityfiber system, the postprandial rise in blood glucose was reduced(P<0.05) at 15, 30, 45, and 60 min. In addition, there was a slower latepostprandial decrease in blood glucose as shown by higher (P<0.05) bloodglucose concentrations at 120 and 180 min, indicating slower andprolonged carbohydrate absorption.

Subjective reports of gastrointestinal symptoms (intensity and frequencyof nausea, cramping, distention and flatulence) 24 h post MGTT arepresented in Table 9.

TABLE 9 Gastrointestinal tolerance of subjects consuming carbohydratebeverages in a meal glucose tolerance test Treatment Control IVIntensity of Nausea 1 ± 0.2 1 ± 0.3 Cramping 1 ± 0.5 5 ± 2.9 Distension0 ± 0.2 4 ± 2.6 Flatulence 2 ± 1.7 5 ± 3.0 Frequency of Nausea 0 ± 0.2 1± 0.4 Cramping 0 ± 0.2 5 ± 3.0 Distension 1 ± 0.2 2 ± 1.5 Flatulence 2 ±1.7 6 ± 3.2 *Mean ± SEM, A score of 5 or less was considered notphysiologically meaningful.

Subjects reported a higher intensity and frequency of cramping,distension, and flatulence when they consumed the polymer controlledinduced viscosity fiber system containing products. The relatively largestandard errors indicate that certain individuals were more susceptiblethan others.

Subjective ratings of hunger during the 3-h MGTT and immediately beforeand after their lunch meal were similar among groups. In addition, theestimated amount of food consumed during the lunch meal following theMGTT was similar among groups.

Conclusion

In conclusion, polymer controlled induced viscosity fiber systemprovided a means to maintain blood glucose levels by reducing the earlyphase excursion and by appropriately maintaining the later phaseexcursion in healthy nondiabetic humans. Healthy nondiabetic subjectsreported a higher intensity and frequency of cramping, distension, andflatulence when they consumed the polymer controlled induced viscosityfiber system containing products.

Experiment 6

The objectives of this animal study were to determine the effect of anutritional product containing the polymer controlled induced viscosityfiber system (IV) of the instant invention on gastric emptying,gastrointestinal motility, and glycemic response. Specifically, theseobjectives were met by determining the effect of the IV containingproduct on myoelectrical activity of the stomach, small intestine andcolon. Parameters that were analyzed included: the percentage of regularslow waves, the percentage of dysrhythmia, the frequency and amplitudeof the slow wave, the coupling and propagation of the slow wave. Theeffect of the IV containing product on contractility of the stomach,pylorus, small intestine and colon was also determined. Additionally,the effect of an IV containing product on gastric emptying wasevaluated.

Eight healthy adult female, mongrel dogs weighing between 19 and 27 kgwere used in this study. After an overnight fast, each dog was operatedunder anesthesia. Four pairs of Teflon coated 28 gauge stainless steelcardiac pacing electrodes (A&E Medical, Farmingdale, N.J.) wereimplanted on the serosal surface of the stomach along the greatercurvature at intervals of 4 cm. The most distal pair was located 2 cmabove the pylorus. Electrode pair number 1 (channel 1) was located inthe body of the stomach; electrode pair number 4 (channel 4) was locatedin the distal antrum of the stomach. The distance between the twoelectrodes in a pair was 0.5 cm. The electrodes were brought outpercutaneously through the abdominal wall. An intestinal fistula wasmade in the duodenum (20 cm beyond the pylorus). This fistula was usedto collect gastric contents for the determination of gastric emptying.In addition to the gastric electrodes, two pairs of serosal electrodeswere implanted in the jejunum (at 35 cm and 40 cm from the pylorus).These electrodes were used to assess myoelectrical activity of thejejunum. After surgery, dogs were transferred to a recovery cage. Allstudies were initiated when each dog had completely recovered from thesurgery.

Products were formulated to contain the following caloric distribution:29% kcal from fat, 20% kcal from protein, and 51% kcal fromcarbohydrate. Products were manufactured into 1-L ready-to-feed bottlesunder aseptic conditions. Product caloric density (0.677 kcal/ml) wassuch that 325 ml (11 fl oz) delivered 28 g of available carbohydrate.Three experimental products were tested: control with no galactomannan;formula with 0.78% galactomannan (about 2.5 g); formula with 1.21%galactomannan (about 3.9 g).

This study was a controlled, randomized, three-way crossover. Each dogreceived each treatment, with a minimum of three days between each test.The order of consumption of the products was randomized. Myoelectricalactivity was recorded to establish baseline activity. After thisbaseline recording, the animal was fed the appropriate study product(325 ml of product, which supplied 220 kcal). Following the feeding,myoelectrical activity was recorded and gastric emptying was measuredfor 120 minutes. In addition, a 5 ml subsample of each gastric emptyingcollection was obtained and transferred into a 15 ml centrifuge tube.Samples were quick frozen and stored at approximately −70° C. Thesesamples were shipped to Ross Products Division for analysis ofTheological characteristics.

Gastric Emptying

Each test meal was mixed with 137.1 mg phenol red. The emptied chyme wascollected from the duodenal cannula at 15-minute intervals for theduration of the study. The rate of gastric emptying was assessed bydetermining the volume of chyme and the concentration of the phenol redin each collection.

Gastric and Small Bowel Motility

Gastric motility and small bowel motility was assessed by calculatingspike activity detected from the myoelectrical recording. In thisexperiment, two parameters were used: 1) number of bursts per minute(NBPM): this is an indication of the number of contractions per minute;and 2) number of spikes per minute (NSPM): a sum of total number ofspikes per minute, reflecting the strength of contractions.

Gastric Slow Waves

Gastric Slow Waves were recorded from the four pairs of implantedserosal electrodes using a multi-channel recorder (Acknowledge III, EOG100A, Biopac Systems, Inc. Santa Barbara, Calif.) with a cutofffrequency of 35 Hz. All signals were digitized at a frequency of 100 Hzand stored electronically. Recorded signals were filtered using adigital low pass filter with a cutoff frequency of 1 Hz and down sampledat 2 Hz. Spectral analysis was performed on the recordings and thefollowing parameters were determined:

-   -   1. Dominant Frequency and Power: The frequency at which the        power spectrum of an entire recording had a peak power in the        range of 0.5 to 9.0 cycles per minute is defined as the dominant        frequency. The power corresponding to the dominant frequency in        the power spectrum is defined as the dominant power. Decibel        (dB) units were used to represent the power of the gastric slow        wave. The relationship of the power P in dB and power P′ in the        linear scale is as follows: P=10*log₁₀(P′). A negative value in        the power reflects a power between 0 and 1 in the linear scale.    -   2. Percentage of Normal Slow Waves: This parameter specifies the        regularity of gastric slow waves. In this method, the gastric        myoelectrical recording is divided into 1-minute segments. The        1-minute segment of the recording is defined as normal if its        power spectrum had a clear peak in the 4-6 cycles per minute        frequency range. Otherwise it was defined as abnormal. The        percentage of normal gastric slow waves was determined by        computing the ratio between the number of normal segments and        the total number of segments. The normal frequency range was        defined as 4-6 cycles per minute. The value of the percentage of        normal slow waves presented in the result section is an average        among the 4 channels.    -   3. Percentage of Slow Wave Coupling: A cross-spectral analysis        method was used to calculate the percentage of slow wave        coupling among the 4-channel recordings. It was computed on a        minute-by-minute basis. First, the adaptive running spectral        analysis was performed on each channel minute-by-minute, and the        dominant frequency of the slow wave in each minute of the        recording was derived. The corresponding dominant frequencies of        the slow wave between any two channels were then compared        minute-by-minute. The minute of the slow wave recorded on the        two channels was defined as coupled if their dominant        frequencies were both within the normal frequency range and        their difference was less than 0.2 cycles per minute. The        percentage of slow wave coupling is defined as the ratio between        the number of the time segments during which the recorded slow        waves were coupled and the total number of segments. The value        presented in the result section is an average over the        exhaustive comparisons among the 4 channels.        Intestinal Slow Waves

Intestinal Slow Waves were recorded using the implanted serosalelectrodes and analyzed as described above, and the following parameterswere determined: 1) Dominant Frequency and Power; and 2) Percentage ofNormal Slow Waves.

Rheological Properties of Chyme

A 5 ml subsample of each 15-minute duodenal collection was obtained andtransferred into a 15 ml centrifuge tube. Samples were quick frozen inethanol and dry ice and stored at −70° C. Samples were shipped to RossProducts Division for analysis of rheological characteristics.

Viscosity was measured at 37° C. with a controlled stress rheometer(Model CSL2-50, TA Instruments, New Castle, Del.) using a 4 cm 4 degreecone. Shear rate was swept from 1 to 250 sec⁻¹ over 2 seconds. A 1 mlsample was used for each viscosity measurement. Because some of thesamples contained particulate matter, they were centrifuged slightly atlow rpm to force the larger particles to the bottom of the tube. Theupper layers were mixed by hand before sampling.

In vitro viscosity was determined by adding 20 μl of alpha-amylase(Sigma #A 3306) to 250 grams of product. This was then incubated at 40°C. for 30 minutes. At the end of 30 minutes, the mixture was agitated atlow rpm for 30 seconds. Viscosity was then measured as described above.

Results

Gastric emptying was significantly delayed by both 0.78% galactomannanand 1.21% galactomannan containing products starting from minute 15compared with the control session (p<0.02,ANOVA) (see FIG. 3).

The NBPM did not show any significant postprandial change in any of thetreatments. Neither was there a difference at any postprandial periodamong the 3 treatments. These data suggest that the frequency of gastriccontractions was not affected by the ingestion of the test meal or thecomposition (fiber) of the meal.

The NSPM (strength of contractions) was significant increasedpostprandially (during the first hour) in the control session but not inthe other treatment sessions. There was no significant difference in theNSPM at any time among the 3 treatments.

A significant postprandial increase (p<0.05) was noted in the NBPM(frequency of intestinal contractions) with 0.78% and 1.21% ofgalactomannan. This increase was however, absent in the control session(see FIG. 4). No difference was observed in the NBPM at any recordingtime among the 3 treatments.

Similarly, there was a significant increase (p<0.05) in the NSPM(strength of intestinal contractions) with 0.78% and 1.21% ofgalactomannan but not in the control session. In addition, the NSPMduring the last 30 minutes of the postprandial recording with 0.78% ofgalactomannan was significantly higher than that in the correspondingperiod of the control session (see FIG. 5).

The dominant frequency of gastric slow waves did not show anysignificant postprandial change in any of the treatments. Neither wasthere a difference at any postprandial period among the 3 treatments.These data suggest that the dominant frequency of gastric slow waves wasnot affected by the ingestion of the test meal or the composition(fiber) of the meal.

The dominant power of gastric slow waves did not show any significantpostprandial change in any of the sessions. Neither was there adifference at any postprandial period among the 3 treatments. These datasuggest that the amplitude of gastric slow waves was not affected by theingestion of the test meal or the composition (fiber) of the meal.

The percentage of normal slow waves did not show any significantpostprandial change in any of the sessions. Neither was there adifference at any postprandial period among the 3 treatments. These datasuggest that the regularity of gastric slow waves was not affected bythe ingestion of the test meal or the composition (fiber) of the meal.

Slow wave coupling did not show any significant postprandial change inany of the sessions. Only the slow wave coupling during the last 30minutes of the postprandial recording with 1.21% of galactomannan wassignificantly higher than that in the corresponding period of thecontrol session. These data imply that the test meal or the composition(fiber) of the meal did not affect the propagation of gastric slow wavesduring one hour after meal.

Intestinal slow waves were recorded using 2 pairs of small bowelelectrodes and the data presented below reflect the averaged valuesbetween the 2 channels.

Small bowel dominant frequency did not show any significant postprandialchange in any of the sessions. Neither was there a difference at anypostprandial period among the 3 treatments. These data suggest that thedominant frequency of intestinal slow waves was not affected by theingestion of the test meal or the composition (fiber) of the meal.

The dominant power of intestinal slow waves did not show any significantpostprandial change in any of the sessions. Neither was there adifference at any postprandial period among the 3 treatments. These datasuggest that the amplitude of intestinal slow waves was not affected bythe ingestion of the test meal or the composition (fiber) of the meal.

Percentage of normal slow wave in the small bowel didn't change in anyof the study sessions after meal compared with fasting state. Neitherwas there a difference at any postprandial period among the 3treatments. These data suggest that the regularity of intestinal slowwaves was not affected by the ingestion of the test meal or thecomposition (fiber) of the meal.

FIG. 6 plots the mean viscosity of the studied formulas at a shear rateof 30 sec⁻¹ at each collection time. It can be seen that the meanviscosity of the 0.78% galactomannan and 1.2% galactomannan is greaterthan the control product.

The in vitro viscosity of the 0.78% galactomannan product at a shearrate of 30 sec⁻¹ was 706 cps, for the 1.2% galactomannan product thisvalue was 890 cps.

Conclusions

The results showed that the induced viscosity products (both 0.78%galactomannan and 1.21% galactomannan) delayed gastric emptying. Inaddition, there was a postprandial enhancement of small bowel (but notgastric) motility with these products, which was not seen in the controlsession.

1. A ready-to-feed liquid composition comprising: (a) protein whichrepresents from about 10 to about 35% of total calories, (b) fat whichrepresents less than about 37% of total calories, and (c) carbohydratewhich represents from about 25% to about 75% of total calories, saidcarbohydrate including a polymer controlled induced viscosity fibersystem which represents at least 30 w/w % of total carbohydrates in theliquid composition, the fiber system including (d) neutral solubledietary fiber selected from the group consisting of guar gum, pectin,locust bean gum, methylcellulose, and mixtures thereof, and (e)hydrolyzed starch having a DP of at least 10 in a weight ratio of theneutral soluble fiber to the hydrolyzed starch of from about 0.35:5.0 toabout 1:5.0 wherein the liquid composition has a ready-to-feed viscosityof less than 200 cps and an in vivo viscosity of at least 300 cps. 2.The liquid composition of claim 1 wherein the hydrolyzed starch has a DPof at least about
 20. 3. The liquid composition of claim 1 wherein thehydrolyzed starch has a DP of from about 30 to about
 100. 4. The liquidcomposition of claim 1 wherein the neutral, soluble, dietary fibercomprises guar gum.
 5. The liquid composition of claim 4 wherein thecomposition comprises at least about 1 w/w % guar gum.
 6. The liquidcomposition of claim 1 wherein the weight ratio of neutral soluble fiberto lightly hydrolyzed starch is from about 0.7:5.0 to about 1:5.0. 7.The liquid composition of claim 1 wherein the composition has aready-to-feed viscosity of from about 50 cps to about 150 cps.
 8. Theliquid composition of claim 1 wherein the composition has an in vivoviscosity of at least 1000 cps.
 9. The liquid composition of claim 1wherein the hydrolyzed starch is maltodextrin.
 10. A method forassisting a diabetic patient with managing their blood glucose levelscomprising feeding said patient the liquid composition of claim
 1. 11. Amethod for producing satiety in a human comprising feeding said humanthe liquid composition of to claim
 1. 12. A method for assisting a humanto lose weight comprising feeding said human the liquid composition ofclaim
 1. 13. A method of promoting the feeling of fullness in a humancomprising feeding to said human the liquid composition of claim 1.